As you can see from our audience this morning, decked out in spy gear. Anticipation building for the hot, new miniseries, "the assets." If you like secrets, spies and lies, this show has it. We're going to talk to the star and the woman who tracked down one of the biggest traitors in our country's history. First, abc's dan harris with the story behind "the assets." Reporter: What you are watching is inspired by real-life events. One of the worst acts of treason in american history. At the height of the cold war, a cia officer walks into the russian embassy in washington, d.C., Hands over a treasure trove of secrets and demands a meeting with the kgb. My name is aldrich ames. I work for the cia. Reporter: This betrayal is at the heart of the new abc miniseries, "the assets." I think you'll want to meet with me after he reads this. Reporter: It is based on the real-life case of aldrich ames, a cia mole who shocked the nation. Tonight, aldrich ames. Reporter: And was covered extensively ly ly by abc news, inclu including this interview by ted koppel. What you did, you did for money. Reporter: "The assets," takes us inside the hunt to track down ames, which was led, in part, by sandy grimes. IT WAS JUNE 13th, 1985, THAT Aldrich ames, everyone knew as rick, gave the kgb ever known human asset that the cia had in the soviet union. It didn't take long for grimes to start to suspect rick ames. But bringing ames down would prove to be tricky and treacherous work. A story brought to life in "the assets." For "good morning america," dan harris, abc news, new york. We're joined by the former cia agent who exposed the traitor, sandy grimes and wrote the book that the miniseries is based on. And paul rhys, the actor,ho ditched the trench coat and glasses. You were the agent that first suspected this guy was a traitor. Do you remember to this day what it felt like on the inside, the moment you started to suspect? All I felt, all I thought about, were the victims. Those people who were executed because of his treason. That was my thoughts. Among the soviets. Among the soviets who were spying on behalf of the united states government. And it's their story that's being told tonight. Paul, you didn't get a chance to meet aldrich. But I understand you tried. I tried. You had to rely on sandy's book? I loved sandy's book and other books. They were very authoritative and knew a great deal. My job is to find the human being underneath the traitor, which wasn't that hard to do because he was driven by greed and love, just like the rest of us. He wanted to impress his new wife, right? Yes, he did. He felt not quite worthy of her. I suspect he would not have committed treason if it wasn't for her. Sandy, I'm curious. You were a mom and a wife at the time, obviously. You had to try to keep this secret from your family about your real-life role at work. Yes. How did you do it? Easy. Just play mom. What did they think you were doing? They didn't care. They were older girls, older teenagers. And their life centers around them. So, mom didn't have to talk about anything except ask them where they were going at night and reminding them what time they had to be home. Your husband was fooled, too? He knew, obviously, I worked at the cia. And knew I worked on soviet matters. But other than that, he had no idea. And he, also, knew rick. Yes. He was very surprised the day he heard that rick ames had been arrested for treason. Was he surprised when he learned the cia agent that brought him down was his wife? He wasn't. He happened to be on a business trip in california. And I told him before he left that morning, please, listen to the news. And paul, so much attention on the series "homeland," which is a huge success. But this is the real thing. It's a real story. It's the most exciting script I've ever read. And it was all the more exciting because it's real. Every event that happened over highly dramatic is real. You do a great job. Sandy, thank you for your work and the book. I can't wait for this to premiere tonight. "The assets," 10:00 eastern, 9:00 central, on abc. Participate in a session on redit, at 9:30 eastern. Good luck tonight. I'll be watching.

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